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  <meta charset="UTF-8">
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  <title>Document</title>
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  <script>
    // 1.var声明的变量会进行作用域的提升
    console.log(message)
    var message = 'hello world'

    // 2.let/const声明的变量:没有作用域提升
    // 有被创建出来,但是无法访问
    // console.log(info)
    let address = '广州市'
    const info = {}

    
  </script>
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